The coking of blends of petroleum residues with coal, coal chars, graphite fines, catalyst fines, and similar solids is well known.
U.S. Pat. No. 1,986,593; Morrell; discloses a cracking process which comprises as a portion of the process charging to a cracking chamber a mixture of 50% fuel oil and 50% raw coal. The blend is fed through a heating zone of 650.degree. F. (343.degree. C.) into an enlarged cracking chamber, thereafter, a portion of the volatiles from the cracking process are admixed with an inferior grade distillate and the mixture heated to about 1,000.degree. F. (538.degree. C.) and added to the oil-coal mixture in the cracking chamber.
U.S. Pat. No. 2,358,573; Hemminger; discloses viscosity breaking a reduced crude in the presence of a powdered carbonaceous material, as for example, granular petroleum coke.
U.S. Pat. No. 2,640,016; Martin; discloses the manufacture of metallurgical coke by coking a mixture of high volatile caking coal and from about 5 to about 25% petroleum coke at from about 892.degree. C. to 1,204.degree. C.
U.S. Pat. No. 3,673,080; Schlinger and Kaufman; discloses the delayed coking of high boiling liquid petroleum feedstocks in the presence of soot, particulate carbon, or catalyst fines in an amount of from about 0.01 to about 0.5 weight percent of the charge to manufacture a high compressive strength, high density, low porosity coke in clustered pellet form.
U.S. Pat. No. 3,704,224; Scovill and Day; discloses the coking of a petroleum feedstock containing catalyst fines of 0.005% and additional colloidal graphite.
U.S. Pat. No. 3,852,047; Schlinger, et al.; discloses the manufacture of clusters of petroleum coke by dispersing from about 0.01 to about 0.5 weight percent of a particulate carbon soot from the partial oxidation of fossil fuel into a petroleum resid and coking the charge in a delayed coking process.
U.S. Pat. No. 3,870,621; Arnold; discloses the fluid coking of a 50:50 mixture of non-caking coal and a residual petroleum fraction at from about 700.degree. F. to about 900.degree. F. (371.degree. C. to 482.degree. C.).
Japanese patent publication (Kokai) 51/112802; discloses mixing a caking coal with a petroleum-derived heavy oil in an amount of from 0.3 to 1.0 times the weight of oil, heating with stirring the mixture at from 400.degree. C. to 450.degree. C. to disperse the coal and prevent separation, then coking the mixture at abote 500.degree. C.